Traditional light sources such as the incandescent lamp, fluorescent lamp, and compact fluorescent lamp will stop emitting light at the end of its life. Thus, the method used to determine whether such a lamp has burnt out or not is very straightforward. In contrast, the LED luminaire uses an LED light source which behaves differently from the traditional light source in that 1) The LED light source does not cease to emit light for a very long time unless the driver of the LED light source failed, 2) the light efficacy of an LED light source decays gradually over time, e.g., dropping to 85% after 30,000 hours and to 70% after 50,000 hours of operation. This amounts to a daily efficacy decay rate of 0.017% (=30%/365/5) which is not discernable by human eye. As a result, a user under such a slowly decaying light source would not notice the 30% drop in light efficacy that would take place over a period of 5 years. This leads to the danger of a user being exposed to a poorly lit environment without knowing it.
Although most traditional light sources also possess the efficacy decay problem, they usually fail sooner than the light output drops to a significantly low level. Therefore their lumen degradation is less an issue compared to that of LED light source.
As user begins to use LED luminaires in over multiple locations on different equipment, it becomes very difficult to track down the operation time of each LED light source and its driver in an LED luminaire. It is equally challenging to determine the remaining lifetime of an LED light source until its lumen output drops to 70%. Best lighting practices generally recommends a lamp replacement when the lumen output falls below 70% of its original level. Working in a poorly lit environment for an extended period of time affects negatively a worker's vision and health. In the application of lighting up equipment such as vending machine or ATM machine, a poorly lit LED light reduces operability of the equipment and customer satisfaction.
The present disclosure provides a lumen maintenance monitoring system that can proactively track the operation time of each LED light source and driver registered with the system. It can alert a user when an LED lighting source is about to drop below a predefined lumen maintenance ratio or a driver is about to reach the end of its operation life. The system can also generate a maintenance schedule for preventative replacement of LED light sources and drivers, thus reducing the maintenance cost and keeping adequate light level where the LED lights are used at all time. Additionally, the lumen maintenance monitoring system has the flexibility of being deployed locally or over the Internet as a cloud service.
The present disclosure enables the lumen maintenance monitoring of LED lamps and drivers in a cost-effective and manageable manner, reduces the potential risk of user vision damage due to insufficiently lit LED lights, thereby protects facilities owners from related liabilities, and helps to uphold the quality and service image of the business entities that depend on well-lit LED lights for their products and services.